On 13 August 2013 19:02, Viresh Kumar [off-list ref] wrote:

Currently prototype of cpufreq_drivers target routines is:

int target(struct cpufreq_policy *policy, unsigned int target_freq,
        unsigned int relation);

And most of the drivers call cpufreq_frequency_table_target() to get a valid
index of their frequency table which is closest to the target_freq. And they
don't use target_freq and relation after it.

So, it makes sense to just do this work in cpufreq core before calling
cpufreq_frequency_table_target() and simply pass index instead. But this can be
done only with drivers which expose their frequency table with cpufreq core. For
others we need to stick with the old prototype of target() until those drivers
are converted to expose frequency tables.

There are 7 drivers after this patchset which still use the heavy weight
version, i.e. target() and 44 drivers have adopted this new approach, i.e.
target_index().

Once those 7 drivers are also moved to use .target_index(), .target() will be
removed completely.

At a quick look at the status of drivers using target_index() it looks there is
scope of more optimizations around that part..

We can actually get rid of cpufreq_notify_transition() from those cpufreq
drivers and do that in core.. And that would cut down size of ->target_index()
routines even more :)

I will give it a try soon.